Device for maintaining urinary continence

ABSTRACT

A prosthetic device for controlling urinary continence is disclosed. The device has an opening pressure that varies in response to changes in physiologic parameters. The device can be controlled by the patient voluntarily without manual intervention. An introducer for transurethrally introducing the device is also disclosed. In addition, a nonsurgical or minimally invasive method of positioning the device for maintaining urinary continence is disclosed.

This application is a divisional of U.S. application Ser. No.08/917,573, filed on Aug. 11, 1997, which is a continuation-in-part ofU.S. application Ser. No. 08/696,333, filed Aug. 13, 1996, now U.S. Pat.No. 5,982,916, the disclosure of which is incorporated herein byreference.

FIELD OF THE INVENTION

The present invention relates to the field of prosthetic urethral valvesor seals for controlling urinary continence. More particularly, thepresent invention relates to a prosthetic urethral device having anopening pressure that varies in response to changes in physiologicparameters. The present invention also relates to an introducer fortransurethrally introducing the prosthetic device in a nonsurgical orminimally invasive procedure.

BACKGROUND OF THE INVENTION

Urinary incontinence is a widespread problem in the United States andthroughout the world. Urinary incontinence affects people of all agesand can severally impact a patient both physiologically andpsychologically. Urinary incontinence has a number of causes, includingbirth defects, disease, injury, aging, and urinary tract infection.

In light of the foregoing, a number of attempts have been made to combaturinary incontinence. One such attempt involves the use of a catheterconnected to a collection bag with a clamping device on the catheter.Indwelling catheters, however, have a number of drawbacks. For instance,there is an infection risk associated with indwelling catheters, whichprovide a direct passage for bacteria or other microorganisms into thebladder. Thus, indwelling catheters can only be used for relativelyshort-term situations. In addition, indwelling catheters and associatedcollection bags are not cosmetically appealing to most patients.

Prosthetic urethral valves of the prior art for controlling incontinencealso have numerous disadvantages. For instance, many prior art urethralvalves utilize an inflatable cuff around the outside of the urethra. Onedisadvantage of such a valve is that it requires surgery forinstallation. In addition, such a valve must be operated externally andthus is dependent on manual intervention.

Intraurethral valves of the prior art also generally require manualintervention. Another problem associated with intraurethral valves isthat they may be displaced into the bladder or expelled from theurethra. There is also an infection risk associated with many suchvalves since they extend into the meatus and/or have portions of thedevice external to the urethra providing a passage for micro-organismsinto the bladder.

Thus, there remains a need for a nonsurgically installed prostheticurethral valve or seal that responds to physiological conditions andthus can be controlled voluntarily by the patient without manualintervention.

SUMMARY OF THE INVENTION

In one aspect of the present invention, there is provided a prostheticurethral valve assembly. The valve assembly includes a tubular bodyhaving a proximal end, a distal end, and a central lumen extendingtherethrough. Attached to the proximal end of the tubular body is afirst anchor. The first anchor conforms to a portion of the base of thebladder so that the prosthetic urethral valve assembly remains properlylocated relative to the bladder and the urethra. The valve assembly alsoincludes a second anchor, which is attached to the tubular body at apoint between the proximal end and the distal end of the tubular body.The second anchor lies within the urethra and helps to anchor the valveassembly therein. The valve assembly also includes a valve, which can belocated within the lumen of the tubular body between the proximal endand the distal end of the tubular body. When positioned in the patient,the distal end of the tubular body is disposed in the midurethra, suchas between the internal urethral sphincter and the external urethralsphincter or introitus so that the opening pressure of the valve variesin response to changes in physiologic parameters.

Another aspect of the present invention relates to a method ofmaintaining urinary continence in a patient. The method includespositioning the prosthetic urethral valve assembly of the presentinvention in a patient so that the distal end of the tubular body andpreferably the valve lie in the midurethra, such as between the internalurethral sphincter and the external urethral sphincter so that theopening pressure of the valve varies in response to changes inphysiologic parameters. For example, the opening pressure of the valvecan vary in response to pressure exerted on the urethra caused by a risein abdominal pressure.

Another aspect of the present invention relates to a method of varyingthe opening pressure of a prosthetic urethral valve in response tochanges in abdominal pressure. The method includes providing aprosthetic urethral valve having a proximal end, a distal end, and avalved flow path therebetween. The valve is positioned in a patientwithin the flow path between the bladder and the outside of the patient.Preferably, the valve is positioned in the patient within the urethrabetween the internal sphincter and the external sphincter. The methodalso includes exposing the distal side of the valve to elevations inintraabdominal pressure and increasing the opening pressure of the valvein response to elevations in intraabdominal pressure.

In accordance with another aspect of the present invention, there isprovided an intraurethral device for maintaining urinary continence. Thedevice in accordance with this aspect of the present invention ispreferably valveless. The device includes a tubular body having aproximal end, a distal end, and a central lumen extending therethrough.Attached to the proximal end of the tubular body is a first anchor,which conforms to a portion of the base of the bladder so that thedevice remains properly located relative to the bladder and the urethra.The device is made of a substantially compliant material so that thetubular body of the device reversibly seals in response to internalforces affecting the urethra and bladder neck. For instance, whenmicturition is undesired, the tubular body of the device reversiblyseals in response to inwardly directed urethral forces, therebymaintaining urinary continence. The tubular body of the device can alsoreversibly seal by kinking in response to rotational descent of thebladder neck and urethra, thereby maintaining continence, such as inpatients suffering from incontinence caused by hypermobility and/or weakpelvic floor muscles.

Another aspect of the present invention relates to an alternateembodiment of the intraurethral device for maintaining urinarycontinence. The device includes a tubular body having a proximal end, adistal end, and a central lumen extending therethrough. The tubular bodyhas a shape which conforms to the urethra. The device also includes afirst anchor which is attached to the tubular body. The first anchor ispreferably attached to the proximal end of the tubular body. The firstanchor conforms to a portion of the urethra, preferably the proximalurethra, to resist migration of the intraurethral device relative to theurethra. The device may also include a second anchor attached to thetubular body. The device is made of a substantially compliant materialso that portions of the device, such as the tubular body and/or firstanchor, reversibly seal in response to anatomical forces affecting theurethra and bladder neck.

In accordance with another aspect of the present invention there isprovided a combination of a device for treating urinary incontinence andan introducer for transurethrally introducing the device. The introduceris an elongate generally tubular structure having a first end, a secondend, and a central lumen extending therethrough. The tubular structurepreferably has a variable diameter. The variable diameter feature of thetubular structure may be accomplished by providing the wall of thetubular structure with a longitudinally extending split. The split mayextend partially or fully along the length of the wall of the tubularstructure. The variable diameter of the tubular structure allowsexpansion of the tubular structure to facilitate loading and deploymentof the device. The variable diameter of the tubular structure alsoallows contraction of the tubular structure during transurethralintroduction of the device to minimize urethral trauma and patientdiscomfort.

Another aspect of the present invention relates to a method ofmaintaining urinary continence in a patient. The method involves usingan introducer to transurethrally introduce a device for maintainingurinary continence which is made of a substantially compliant materialso that the device reversibly seals in response to anatomical forcesaffecting the urethra and bladder neck. The device for maintainingurinary continence can be provided to the physician in a variety oflengths so that the physician can choose an appropriate device for agiven patient. If necessary, the device can also be cut to length by thephysician based on the patient's measured urethral length. Preferably,the length of the device is less than the patient's urethral length.After loading the device into the introducer, the physician inserts theloaded introducer into the urethra so that a first end of the introducerextends into the bladder. The device is then displaced out of theintroducer and into the bladder. The physician then withdraws theintroducer from the patient and withdraws the device until the device ispositioned within the flow path between the bladder and introitus,thereby maintaining urinary continence. Preferably, the device iswithdrawn until the entire device is positioned within the urethra. Theintroducer used in accordance with this method may also include agenerally tubular structure having a variable diameter. In such cases,the tubular structure can be expanded to increase the diameter of theintroducer to facilitate loading and displacement of the device formaintaining urinary continence. The tubular structure can also becontracted to decrease the diameter of the introducer, such as duringtransurethral insertion of the loaded introducer to minimize urethraltrauma and patient discomfort.

In accordance with another aspect of the present invention, there isprovided a method of positioning a device for maintaining urinaryincontinence in a patient. The device for maintaining urinary continenceis coupled to a locating device having an expandable tip, such as aballoon catheter, so that the proximal end of the device for maintainingurinary continence is separated a preselected distance from theexpandable tip of the locating device. The coupled device formaintaining urinary continence and locating device is transurethrallyintroduced so that at least the expandable tip of the locating deviceextends into the bladder. The expandable tip of the locating device isthen expanded from a non-expanded configuration to an expandedconfiguration. The coupled device for maintaining urinary continence andlocating device is then withdrawn until the expanded tip of the locatingdevice contacts the bladder neck so that the device for maintainingurinary continence is properly positioned within the urinary tract. Theexpandable tip is then returned to the non-expanded configuration, thedevice for maintaining urinary continence is decoupled from the locatingdevice, and the locating device is removed from the patient, leaving thedevice for maintaining urinary continence properly positioned within theurinary tract of the patient.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of the prostheticurethral valve according to the present invention.

FIG. 2 is a bottom view of the valve depicted in FIG. 1.

FIG. 3 is an elevational cross-sectional view taken along line 3--3 ofFIG. 2.

FIG. 4 is a transverse cross-sectional view through the bladder showinga top view of the device positioned in the bladder.

FIG. 5 is an elevational cross-sectional view taken along line 5--5 ofFIG. 4.

FIG. 6 graphically depicts the relationship between urethral pressureand urethral length in a group of symptom-free women and four groupswith stress incontinence of varying severity.

FIGS. 7A and 7B diagrammatically represent the bladder, the urethra, andvarious pressures relating to urinary tract physiology.

FIG. 8 is a perspective view of an alternate embodiment of theprosthetic urethral valve according to the present invention.

FIG. 9 is a bottom view of the valve depicted in FIG. 8.

FIG. 10 is an elevational cross-sectional view taken along line 10--10of FIG. 9.

FIG. 11 is a transverse cross-sectional view through the bladder showinga top view of the alternate embodiment of the device positioned in thebladder.

FIG. 12 is an elevational cross-sectional view taken along line 12--12of FIG. 11.

FIG. 13 illustrates the valve assembly of FIG. 12 during a hypermobilityevent.

FIG. 14 is a cross-sectional view taken along line 14--14 of FIG. 12.

FIG. 15 is a cross-sectional view taken along line 15--15 of FIG. 13.

FIG. 16 is a partially exploded side view of various components of adevice for installing the prosthetic urethral valve of the presentinvention.

FIG. 17 is a side view of the grasping forceps extending distally fromthe cystoscope to releasably engage the prosthetic urethral valve of thepresent invention.

FIG. 18 is a perspective view of an alternate embodiment of the deviceaccording to the present invention.

FIG. 19 is a bottom view of the embodiment depicted in FIG. 18.

FIG. 20 is an elevated cross-sectional view taken along line 20--20 ofFIG. 19.

FIG. 21 is a perspective view of an alternate embodiment of the deviceaccording to the present invention.

FIG. 22 is a top view of the embodiment depicted in FIG. 21.

FIG. 23 is an elevational side view of the embodiment depicted in FIG.21.

FIG. 23A is an elevational side view of an alternate embodiment of thedevice depicted in FIG. 23.

FIG. 24 is a bottom view of the embodiment depicted in FIG. 21.

FIG. 25 is a cross-sectional view taken along line 25--25 of FIG. 22.

FIG. 26 is a cross-sectional view of an alternate embodiment of thedevice illustrated in FIG. 25.

FIG. 27 is a cross-sectional view taken along line 27--27 of FIG. 25.

FIG. 28 is a cross-sectional view of an alternate embodiment of thedevice illustrated in FIG. 25 showing an alternate shaped tubular body.

FIG. 29 is a cross-sectional view of an alternate embodiment of thedevice illustrated in FIG. 25 showing an alternate shaped tubular body.

FIG. 30 is a cross-sectional view of an alternate embodiment of thedevice illustrated in FIG. 25 showing an alternate shaped and variablestiffness tubular body in a closed position.

FIG. 31 is a cross-sectional view of an alternate embodiment of thedevice illustrated in FIG. 25 showing an alternate shaped and variablestiffness tubular body in an open position.

FIG. 32 is an elevational side view of an alternate embodiment of thedevice according to the present invention.

FIG. 33 is a top view of the embodiment depicted in FIG. 32.

FIG. 34 is a bottom view of the embodiment depicted in FIG. 32.

FIG. 35 is a perspective view of an alternate embodiment of the deviceaccording to the present invention.

FIG. 36 is a top view of the embodiment depicted in FIG. 35.

FIG. 37 is an elevational side view of the embodiment depicted in FIG.35.

FIG. 38 is a bottom view of the embodiment depicted in FIG. 35.

FIG. 39 is a frontal perspective view of an alternate embodiment of thepresent invention showing a resilient support structure embedded in adevice which is shown in phantom.

FIG. 40 is a cross-sectional view taken along line 40--40 of FIG. 39.

FIG. 41 is a frontal perspective view of an alternate embodiment of thepresent invention showing a resilient support structure inserted in thelumen of a device which is shown in phantom.

FIG. 42 is a cross-sectional view taken along line 42--42 of FIG. 41.

FIG. 43 is a side view of the resilient support structure depicted inFIG. 41.

FIG. 44 is a frontal perspective view of an alternate embodiment of thedevice illustrated in FIG. 41.

FIG. 45 is a cross-sectional view taken along line 45--45 of FIG. 44.

FIG. 46 is a perspective view of a resilient support structure of thepresent invention inserted in a urethra which is shown in phantom.

FIG. 47 is an alternate embodiment of the resilient support structureshown in FIG. 46 inserted in a urethra which is shown in phantom.

FIG. 48 is a side view of the resilient support structure shown in FIGS.46 and 47.

FIG. 49 is a schematic elevational cross-sectional view showing acollapsible duckbill valve in a closed position. The open position ofthe valve is shown in phantom.

FIG. 50 is a schematic cross-sectional view showing an alternateembodiment of a valve-like structure of the present invention in an openposition.

FIG. 51 is a schematic cross-sectional view showing the valve-likestructure of FIG. 50 in a closed position.

FIG. 52 is a schematic elevational cross-sectional view showing atethered ball type valve in a closed position.

FIG. 53 shows the valve of FIG. 52 in an open position.

FIG. 54 is an alternate embodiment of the valve illustrated in FIGS. 52and 53.

FIG. 55 is an exploded side view showing a device for maintainingurinary continence, an introducer, and a balloon catheter coupled tograsping forceps.

FIG. 56 is a bottom view of the introducer taken along line 56--56 ofFIG. 55.

FIG. 57 is a cross-sectional view of the introducer taken along line57--57 of FIG. 55.

FIG. 58 is a schematic cross-sectional view showing the introducer in anexpanded configuration.

FIG. 59 is a schematic cross-sectional view showing the introducer in acontracted or overlapping configuration.

FIG. 60 is an assembled side view showing the device for maintainingurinary continence, balloon catheter, and grasping forceps inserted intothe introducer.

FIG. 61 is a schematic cross-sectional view showing the loadedintroducer inserted into the urethra and bladder.

FIG. 62 is a schematic cross-sectional view showing the balloon catheterbeing advanced out of the introducer and into the bladder.

FIG. 63 is a schematic cross-sectional view showing the balloon catheterand device for maintaining urinary continence being displaced from theintroducer into the bladder.

FIG. 64 is a schematic cross-sectional view showing the introducer beingwithdrawn from the urethra and the balloon being inflated within thebladder.

FIG. 65 is a schematic cross-sectional view showing withdrawal of thecoupled grasping forceps and balloon catheter with the inflated ballooncontacting the bladder neck.

FIG. 66 is a schematic cross-sectional view showing the device formaintaining urinary continence positioned in the urinary tract of thepatient.

FIG. 67 is a perspective end view showing a tether attached to thedistal end of a tubular body of the device for maintaining urinarycontinence.

FIG. 68 is a schematic cross-sectional view showing the device formaintaining urinary continence being placed in an alternative positionin the urinary tract.

FIG. 69 is a schematic cross-sectional view showing the device formaintaining urinary continence positioned within the urinary tract afterremoval of the balloon catheter and grasping forceps illustrated in FIG.68.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, there is disclosed a perspective view of theprosthetic urethral valve assembly 10 of the present invention. Thevalve assembly includes a tubular body 12 having a proximal end 18, adistal end 20, and a central lumen 22 extending therethrough. Asillustrated in FIG. 2, a gripping tab or boss 27 is preferably includedat the distal end 20 of tubular body 12 to facilitate transurethralplacement of the valve, which is discussed in more detail below.

The valve assembly 10 also includes a first anchor 14. The first anchorpreferably conforms to a portion of a base 32 of a bladder 30 asillustrated in FIGS. 4 and 5. The first anchor 14 functions toreleasably secure the valve assembly 10 relative to the bladder 30 andthe urethra 40, while preferably avoiding contact with the trigone 34 ofthe bladder 30. The first anchor 14 also helps prevent urine fromescaping around the exterior of the device.

The trigone 34, illustrated in FIG. 4, is a triangular area of thebladder located between the urethra 40 and the two ureteric orifices 38and 39. The ureteric orifices 38 and 39 drain urine from the ureters 36and 37, respectively. Minimizing or avoiding contact between the firstanchor 14 and the trigone 34 is desirable because the trigone contains anerve bed which can be stimulated by tactile means resulting in anundesirable sense of urinary urgency.

In light of the foregoing considerations, the first anchor is preferablyan atraumatic retention structure which is enlargeable from a first,collapsed configuration for transurethral placement to a second,enlarged configuration for resisting distal migration out of the bladderand into the urethra. In the illustrated embodiment, the first anchorcomprises a pliable semiconical retention flap that inclines generallyradially outwardly in the proximal direction from the proximal end 18 ofthe tubular body 12 as illustrated in FIG. 1. The retention flap ismechanically biased in the direction of the second, enlargedconfiguration as illustrated to help prevent the valve assembly 10 frombeing expelled distally from the urethra 40. The proximal surface of thefirst anchor 14 is exposed to the intravesical pressure of the bladder,which helps prevent the valve assembly 10 from being dislodgedproximally into the central portion of the bladder.

In most patients, the trigone extends circumferentially approximately60° to 90°. Thus, if properly placed within the bladder, the firstanchor 14 can extend circumferentially up to as much as fromapproximately 270° to 300° and still avoid contacting the trigone.Preferably, the first anchor extends circumferentially eithercontinuously or intermittently through an angle of approximately 100° to180° in order to account for potential human error during placement, yetstill provide an adequate surface area to achieve the anchoring functiondescribed above. In some embodiments, the construction material of thefirst anchor 14 is such that the anchoring function can be achieved withcircumferential extension of less than about 100°.

A number of structures can be used to minimize either the circumferenceor the total contact area of the first anchor 14 yet still provide foradequate anchoring. For example, circumferentially extending reinforcingrings 15 and/or 17, such as a fine gauge spring wire may be incorporatedinto the valve assembly. The use of spring wires would provide a bias inthe direction of the second, enlarged configuration while permitting areduction in the size and mass of the anchor. Spring wires canalternatively extend in planes that are generally parallel to thelongitudinal axis of the tubular body 12. Wires can be integrally moldedinto the anchor 14. Spring bias can also be optimized simply byadjusting the wall thickness of the anchor 14 and through appropriatematerials choice.

In addition, as will be apparent to one of ordinary skill in the art, avariety of other structures could be used to accomplish the function offirst anchor 14. For instance, the first anchor 14 may comprise a seriesof discontinuous, mechanically biased flexible struts extending from theproximal end 18 of the tubular body 12. Typically, two or three or morestruts would be used. Alternatively, spring biased hinged anchors couldbe used to releasably secure the valve assembly 10 relative to thebladder 30 and the urethra 40.

In addition to the first anchor 14, preferably the valve assembly 10also includes a second anchor 16. The second anchor 16 also helps toreleasably secure the valve assembly 10 relative to the bladder 30 andthe urethra 40. In addition, the second anchor 16 helps to stabilize thetubular body 12 within the urethra, especially in a patient having alarge diameter urethra.

In the illustrated embodiment, the second anchor 16 is an annular flangeattached to the tubular body 12 at a point between the proximal end 18and the distal end 20. As illustrated in FIG. 1, the second anchor rampsradially outwardly in the proximal direction, thereby providing amechanical bias against proximal dislodgement of the tubular body intothe bladder. Optionally, one or more nitinol rings can be molded intothe annular flange. After insertion of the valve assembly, expansion ofthe nitinol rings or other resilient support structures in response tobody temperature provides an additional mechanical bias to help furthersecure the valve assembly.

As will be apparent to one of ordinary skill in the art, a variety ofstructures other than the proximally extending annular flange describedabove could be used to accomplish the function of second anchor 16. Forinstance, a variety of radially extending preferably atraumaticstructures, such as semi-spheres, ridges or barbs can be attached to orintegrally molded with the tubular body 12. Proximally and/or distallyextending suture ends attached to the tubular body 12 using well knownmethods can also be used to accomplish the function of the second anchor16.

The valve assembly 10 also includes a valve 24, such as a duckbillvalve, which is preferably located within the fluid flow path throughtubular body 12 between the proximal end 18 and the distal end 20. Asillustrated in FIG. 3, optional valve supports 26 can also be includedin the present invention to increase the opening pressure of the valve,if necessary, based on the characteristics of the material anddimensions used to construct the valve assembly 10.

The function of the valve is to assist normal physiological mechanismsto regulate the flow of urine through the tubular body 12. When thevalve 24 is in an open position, the tubular body provides a fluidcommunication path between the bladder 30 and the urethra 40. When thevalve is in the open position, preferably a flow rate of approximately5-15 cc per second is achieved when the pressure differential on thevalve is between approximately 20-30 cmH₂ O. When the valve is in aclosed position, the valve assembly 10 provides a seal preventingincontinence.

A variety of structures other than the duck bill valve described abovecould be used to accomplish the function of the valve 24. For instance,the valve 24 could comprise a collapsible duckbill valve such as thatillustrated in FIG. 49. In FIG. 49, the valve 24 is shown in both theopen and closed positions, the open position being shown in phantom. Oneadvantage of the valve 24 illustrated in FIG. 49 is that it has arelatively high opening pressure above which little resistance to flowis encountered.

In addition, a valve-like function could be achieved as illustrated inFIGS. 50-51 in which a solid rod-like structure 65 is placed within thetubular body 12. The rod-like structure 65 is preferably oval asillustrated in FIGS. 50-51. In its open state, the diameter of thetubular body 12 is larger than that of the rod 65. Using conventionaltechniques such as thermal bonding, solvent bonding or suitableadhesives known in the art, the tubular body 12 is secured to the rod 65preferably along the length of the rod 65 at at least two points asillustrated in FIG. 50.

During bladder filling, the urethra exerts radially inwardly directedforces on the tubular body 12 which keep the tubular body 12 sealedagainst the rod 65 as illustrated in FIG. 51, thereby maintainingcontinence. During micturition, however, the pressure exerted by theurethra decreases allowing radial expansion of the tubular body 12 toits open position as illustrated in FIG. 50.

The function of the valve 24 could also be accomplished using a tetheredball type valve as illustrated in FIGS. 52-53. When the valve is in theclosed position, the ball portion 67 of the valve preferably restsagainst an inwardly projecting extension 69 of the tubular body 12 asillustrated in FIG. 52. The ball portion 67 of the valve is attached toan elastomeric tether 71. As will be apparent to one of ordinary skillin the art, the tether 71 can be attached at a variety of places on thevalve assembly 10, such as the proximal end 18 of the tubular body 12 asillustrated in FIGS. 52-53. FIG. 53 shows the valve in the openposition.

FIG. 54 illustrates an alternative embodiment of the tethered ball typevalve. In accordance with this embodiment, when the valve is in theclosed position the area of fluid in contact with the ball portion 67 ofthe valve has a diameter "d" which is less than the diameter "D" of theball portion 67 of the valve. Because the area of fluid in contact withthe ball portion 67 of the valve in the closed position is less than thearea of fluid in contact with the ball portion 67 of the valve when thevalve is in the open position, the pressure required to open the valveis more than the pressure required to keep the valve in the openposition. Thus, little resistance to flow is encountered after theopening pressure is achieved.

As will be apparent to one of ordinary skill in the art, a variety ofstructures other than the valves described above could be used toaccomplish the function of the valve 24. For instance, the valve 24could comprise a trap door type valve with an integral elastomericreturn spring hinge or tether. Such a valve preferably has a relativelyhigh opening pressure, such as from about 5-80 cmH₂ O, and morepreferably from about 5-20 cmH₂ O, above which little resistance to flowis encountered. A multi-leaflet valve having struts to control baselinepressure or a poppet type valve having an integral elastomeric springcould also be used to accomplish the function of valve 24.

For convenience, the valves described above were discussed withreference to valve assembly 10. One of ordinary skill in the art willrecognize, however, that the valves described above can also be usedwith other embodiments of the present invention described in the subjectapplication.

The opening pressure of the valve 24 depends on the type of valve chosenand the etiology of the patient's incontinence. The opening pressure ofthe valve, prior to being positioned within the patient, ranges fromapproximately 2-100 cmH₂ O, more preferably from approximately 5-20 cmH₂O, and most preferably from approximately 5-10 cmH₂ O. As discussedbelow, however, after the valve is properly positioned within thepatient, the opening pressure of the valve varies in response tophysiologic parameters.

Referring to FIG. 5, an elevational cross-sectional view of the valveassembly is shown positioned relative to the bladder 30 and the urethra40. The urethra 40 is diagrammatically divided into a proximal portion48 and a distal portion 50. An internal urethral sphincter 44 and anexternal urethral sphincter 46 are also schematically shown. Asillustrated in FIG. 5, the distal end 20 of tubular body 12 is locatedwithin the proximal portion 48 of the urethra 40 between the internalurethral sphincter 44 and the external urethral sphincter 46.Preferably, the valve 24 is also located in the proximal portion 48 ofthe urethra, although it can alternatively be positioned elsewhere alongthe flow path between the bladder 30 and the distal end 20 of the valveassembly 10. Optionally, a radiopaque material, such as gold, tantalum,or barium sulfate can be incorporated into the valve to ensure properpositioning. Preferably, the radiopaque material is incorporated as avisualization ring into the distal end 20 of the tubular body 12.

Although knowledge of the physiology of the bladder and the urethra isincomplete, the external urethral sphincter is believed to be locatedapproximately 1.0 to 4.0 cm, and more typically approximately 1.5 to 2.5cm, distal to the bladder neck 42 in women, and approximately 5.0 to 6.0cm distal to the bladder neck 42 in men. The external urethral sphincteris believed to primarily be responsible for the urethral pressureprofile illustrated in FIG. 6. As can be seen in FIG. 6, urethralpressure is highest approximately 2 cm distal to the bladder neck. Theinventors believe that in some instances the top portions of the curvesillustrated in FIG. 6 may extend over a larger range of urethral length.In order to fully take advantage of the urethral pressure gradient, thevalve 24 and the tubular body 12 preferably do not extend distal to theexternal urethral sphincter. More preferably, the tubular body 12extends less than or equal to about 2.0 cm distal to the bladder neck.The relatively short length of the tubular body 12 allows the valve tobe maximally exposed to the urethral pressure gradient, thereby aidingin keeping the valve 24 closed while the bladder is filling. Duringmicturition, however, the urethra relaxes, removing this back pressureor closing pressure and aiding in the voiding process.

The urethral pressure gradient described above, also aids the valveassembly 10 in maintaining urinary continence during changes inphysiologic parameters, such as increases in abdominal pressure causedby coughing. This aspect of the present invention is illustrateddiagrammatically in FIGS. 7A and 7B. In FIGS. 7A and 7B, "a" equalsresting intra-abdominal pressure, "b" equals resting bladder pressure,"u" equals resting urethral pressure, and "A" equals abdominal pressurerise on coughing. As can be seen in FIG. 7B, an increase in abdominalpressure increases both the bladder pressure and the urethral pressure.Because of the relatively short tubular body 12 of the presentinvention, however, the increase in urethral pressure caused by theincrease in abdominal pressure is transmitted to the distal side of thevalve 24, thereby momentarily increasing the effective opening pressureof the valve to help maintain valve closure during the increase inabdominal pressure.

In addition to the urethral pressure gradient described above, thebladder neck and the urethra also exert an inwardly directed force,which can enhance the function of the valve assembly 10 of the presentinvention. For instance, during bladder filling, the urethra exertsinwardly directed forces on the tubular body 12 and the valve 24, whichhelp to keep the valve closed during the filling phase.

Conversely, during micturition, the pressure exerted by the bladder neckand the urethra decreases, thereby decreasing the radial or compressiveforce exerted on the tubular body and the valve. This decrease in radialor compressive force lowers the opening pressure of the valve and thusfacilitates opening of the valve during micturition. Thus, although anyof a variety of valve structures can be utilized in the valve assembly10, valve structures which exhibit an increased opening pressure inresponse to inward compressive forces or radially inward compression areoften preferred.

In contrast to the relatively short valve assembly 10 of the presentinvention, prosthetic urethral valve devices that extend into the meatusand/or have portions of the device external to the body are unable totake advantage of the urethral pressure gradient and radial forcesdescribed above.

Another advantage of the relatively short length of the valve assemblyof the present invention is that it minimizes the risk of infection. Incontrast, prosthetic urethral valve devices that extend into the meatusand/or have portions of the device external to the body provide a directpath for bacteria and other microorganisms to enter the urinary tract.

Referring to FIGS. 8-15, there is shown an alternate embodiment of thevalve assembly of the present invention. As illustrated in FIG. 8, thevalve assembly 110 includes a tubular body 112 having a proximal end118, a distal end 120 and a central lumen 122 extending therethrough.The valve assembly also includes a first anchor 114, a gripping boss127, and reinforcing rings 115, 117.

In addition to the first anchor 114, preferably the valve assembly 110also includes a second anchor 116. The illustrated second anchor 116 isan annular flange attached to the tubular body 112 at a point betweenthe proximal end 118 and the distal end 120 of the tubular body. Asillustrated in FIG. 8, the second anchor of the alternate embodimentpreferably inclines distally from tubular body 112, thereby providing amechanical bias against distal dislodgement of the valve assembly fromthe patent.

The valve assembly 110 also includes a valve 124, such as a duckbillvalve, which is preferably located within the lumen 122 of tubular body112 between the proximal end 118 and the distal end 120 of the tubularbody. As illustrated in FIG. 9, the orientation of valve 124 ispreferably rotated approximately 90° relative to the valve depicted inFIG. 2. Thus, the coaptive edges of the two duckbill leaflets extendside to side when the valve is properly positioned in the patient. Inaddition, as illustrated in FIG. 10, optional valve supports 126 can beincluded to increase the opening pressure of the valve, if necessary,based on the characteristics of the material used to construct the valveassembly 110.

The length of the tubular body 112 of the valve assembly of thealternate embodiment is approximately the same as that of the valveassembly of FIGS. 1-5. As illustrated in FIG. 10, however, the distancebetween the valve 124 and the proximal end of the tubular body 112 ofthe alternate embodiment is greater than the distance between the valve24 and the proximal end of the tubular body 12 of the valve assembly 10illustrated in FIG. 3. Preferably the distance between the valve 124 andthe proximal end of the tubular body is approximately 1.0-3.0 cm in thealternative embodiment, compared to approximately 0.5-2.0 cm in theembodiment of the valve 24 depicted in FIG. 3. The increased distancebetween the valve 124 and the proximal end of the tubular body in thealternate embodiment is especially useful in patients suffering fromincontinence caused by hypermobility.

In patients suffering from incontinence caused by hypermobility, thebladder neck and proximal urethra rotate and descend in response toincreases in intra-abdominal pressure. During a hypermobility event, theorientation of the urethra relative to the bladder may change betweenapproximately 20° and 90°. In such patients, rotation and descent of thebladder neck and urethra result in an uneven transmission ofintra-abdominal pressure to the bladder and urethra. This can cause thebladder pressure to exceed the urethral pressure by as much as 100 cmH₂O, resulting in incontinence. As illustrated in FIG. 13, however, theincreased distance between the valve 124 and the proximal end of thetubular body 112 of the alternate embodiment allows the tubular body tokink during a hypermobility event, thereby occluding the lumen of thetubular body, which helps prevent undesired leakage of urine through thevalve assembly.

FIGS. 12 and 13 illustrate the kinking feature of the tubular body 112of the alternate embodiment of the present invention. FIG. 12 is anelevational cross-sectional view of the valve assembly positioned in thepatient prior to a hypermobility event. In contrast, FIG. 13 illustratesthe same view of the valve assembly during a hypermobility event. As canbe seen, during the hypermobility event, the proximal portion of thetubular body 112 kinks or collapses, which helps to maintain continencewithout having to unduly increase the opening pressure of the valve 124.

In order to facilitate kinking of the tubular body 112, the tubular bodypreferably has a thinner wall and/or a non-circular cross section, suchas elliptical or oval, at the desired point of kinking. In manypatients, such as those suffering from incontinence caused byhypermobility, the desired point of kinking would be in the proximalportion of the tubular body approximately 0.1-1.5 cm distal to theproximal end 118 of the tubular body. In some patients, however, thedesired point of kinking may be located elsewhere along the tubular body112 as will be evident to one of skill in the art. In addition, thedevice of the present invention may have a thinner wall and/ornon-circular cross section throughout the length of the tubular body. Atubular body having a non-circular cross section is illustrated in FIGS.14 and 15, which show the lumen of the tubular body before and afterkinking of the tubular body caused by a hypermobility event.

As discussed earlier in connection with the valve assembly of FIGS. 1-5,one of ordinary skill in the art will recognize that a variety ofstructures other than the first anchor 114, second anchor 116, and valve124 illustrated in FIGS. 8-13 could be used in accordance with thealternate embodiment of the present invention.

The valve assembly of the present invention can be manufactured usingany of the variety of means known to those of ordinary skill in the art.Preferably the valve is injection molded into an integral unit.Alternatively, the valve assembly 10, 110 can be fabricated from two ormore separately molded units, which are secured using conventionaltechniques such as thermal bonding, solvent bonding or suitableadhesives known in the art. For instance, the valve 24, 124 and theremainder of the valve assembly 10, 110 could be manufactured separatelyand then combined into a single unit using conventional methods known tothose of ordinary skill in the art.

The device of the present invention may be made of any suitableresilient material which is biocompatible and resistant to a urineenvironment. Preferred materials include silicone rubbers, latex rubbersand polyurethane, with silicone rubbers being the most preferred. Inaddition to facilitating functioning of the device, the choice of soft,resilient materials also enhances patient comfort.

To minimize encrustation and infection, coatings well known to those ofordinary skill in the art, such as silver flouropolymers or sulfatedpolysaccharide pentosan-polysulfate, can be applied to the device.

The dimensions and configuration of the valve assembly 10, 110 can bevaried considerably to suit particular design criteria desired for aparticular application and still embody the present invention.Dimensions are largely limited by anatomical considerations as discussedabove with respect to the length of the tubular body 12, 112, which ispreferably approximately 0.5 cm to 3 cm in length, and more preferablyless than about 1.5 cm in length. The diameters of the tubular body 12,112 and second anchor 16, 116 are also dictated by anatomicalconsiderations. In particular, the diameters of the tubular body andsecond anchor are chosen to fit securely within the urethra yet notexert an excess outward force on the urethra so that the tubular bodycan be compressed in response to urethral forces. Typical ranges for theoutside diameter of the tubular body are approximately 0.5 cm to 0.8 cm(15-24 French), preferably about 0.6 cm (18 French). Typical ranges forthe outside diameter of the second anchor are approximately 0.66 cm to 1cm (20-30 French), preferably about 0.08 cm (24 French). The wallthickness of the tubular body is generally within the range of fromabout 0.15-3 mm, preferably about 0.25-1 mm, and more preferably about0.4 or 0.5 mm.

In addition to anatomical considerations, the size and shape of variouscomponents of the valve assembly 10, 110 are also governed by the typeof material used to construct the valve assembly.

A nonsurgical procedure for maintaining urinary continence in a patient,is generally accomplished as follows. A prosthetic urethral valveassembly such as 10 or 110 of the present invention is selected by thephysician based on the sex of the patient as well as other anatomicaland medical considerations. Using an installation device, such as thecystoscope 221 and grasping forceps 225 illustrated in FIG. 16 anddescribed below, the physician transurethrally positions the prostheticurethral valve assembly so that both the valve 24, 124 and the distalend 20, 120 of the tubular body 12, 112 lie between the internalurethral sphincter and the external urethral sphincter so that theopening pressure of the valve varies in response to changes inphysiologic parameters.

With reference to the installation device depicted in FIG. 16, onemethod of positioning the valve assembly 10, 110 is accomplished asfollows. The physician transurethrally advances the cystoscope 221 androd lens 229 into the bladder in accordance with conventionaltechniques. The physician then performs a standard cystoscopicexamination of the bladder and fills the bladder with an irrigant. Afterperforming the cystoscopic examination, the physician removes thecystoscope 221 from the urethra and removes the rod lens 229 from thecystoscope. The grasping forceps 225 are then passed through thecystoscope 221 so that the forceps 225 extend beyond the distal end 223of the cystoscope 221 as illustrated in FIG. 16. A water solublelubricant, such as K-Y jelly is applied to the outside of the valveassembly. The forceps 225 are used to releasably engage the valveassembly. For example, as illustrated in FIG. 17, the gripping boss 127of the valve assembly is preferably releasably engaged by the forceps225. The physician then carefully pushes the valve assembly into thedistal end 223 of the cystoscope 221, collapsing the valve assembly asneeded. The physician may also gently withdraw the forceps proximally topull the valve assembly into the distal end of the cystoscope.

After placing the valve assembly 10, 110 into the distal end of thecystoscope, the physician passes the cystoscope through the urethra andinto the bladder. Rod lens 229 is then inserted into the cystoscope 221until it contacts the valve assembly. Using the rod lens and the forceps225, the physician axially displaces the valve assembly distally out ofthe distal end 223 of the cystoscope 221 and into the bladder. Whileviewing the valve assembly 10, 110 in the bladder using the rod lens229, the physician can rotate the forceps, if necessary, to properlyorient the valve assembly and the first anchor 14, 114 relative to thebase of the bladder and the trigone region.

While keeping the forceps stationary relative to the cystoscope, thephysician withdraws the cystoscope, proximally thereby placing tractionon the valve assembly in order to lodge the first anchor relative to thebase of the bladder while avoiding contact between the first anchor andtrigone region. Optionally, the position of the valve assembly can beconfirmed using well known radiologic methods, such as in thoseembodiments in which a visualization ring has been incorporated into thevalve assembly.

If the valve assembly is not properly positioned, the physician canreadvance the cystoscope and the valve assembly into the bladder torotate and reposition the valve. After the valve assembly is properlypositioned, the physician releases the valve assembly from the forcepsand withdraws the cystoscope, including the forceps and rod lens, fromthe patient.

The valve assembly 10, 110 can also be positioned using a standardembolectomy balloon catheter rather than the grasping forceps 225described above. After performing a standard cystoscopic examination ofthe bladder and filling the bladder with an irrigant, the physicianremoves the cystoscope 221 from the urethra and removes the rod lensfrom the cystoscope leaving the bridge attached. The balloon catheter isthen passed through the bridge and the cystoscope 221 so that theinflatable portion of the balloon catheter extends beyond the distal end223 of the cystoscope. A water soluble lubricant, such as K-Y jelly, isapplied to the outside of the valve assembly 10, 110. A standard ballooncatheter threading tube is then advanced through the tubular body 12,112 from the proximal end 18. 1 18 to the distal end 20, 120 of thetubular body.

The tip of the balloon catheter is then placed against the threadingtube and the physician gradually extends both the balloon catheter andthreading tube through the valve 24, 124 of the valve assembly 10, 110.The physician then carefully pushes the valve assembly into the distalend 223 of the cystoscope 221, collapsing the valve assembly as needed.After placing the valve assembly into the distal end of the cystoscope,the physician passes the cystoscope through the urethra and into thebladder.

The balloon catheter is then advanced distally so that the inflatableportion of the balloon catheter extends beyond the distal end of thecystoscope. The balloon is then inflated by the physician usingconventional inflation media, such as fluid. The rod lens 229 is theninserted into the cystoscope 221 until it contacts the valve assembly.Using the rod lens (or other push rod structure), the physician axiallydisplaces the valve assembly distally beyond the distal end of thecystoscope and into the bladder where it remains coaxially positionedabout the balloon catheter shaft proximally of the balloon.

While viewing the valve assembly in the bladder using the rod lens, thephysician can rotate the shaft of the balloon catheter, if necessary, toproperly rotationally orient the valve assembly and the first anchor 14,114 relative to the base of the bladder and the trigone region. Duringor after retraction of the cystoscope through the bladder neck, thephysician retracts the inflated balloon catheter proximally in order tolodge the first anchor 14, 114 relative to the base of the bladder whileavoiding contact between the first anchor and the trigone region.Optionally, the axial position of the valve assembly can be confirmedusing well known radiologic methods, such as in those embodiments inwhich a visualization ring has been incorporated into the valveassembly. If the valve assembly is not properly positioned, thephysician can readvance the cystoscope, balloon catheter, and valveassembly into the bladder to reposition the valve. After the valveassembly is properly positioned, the physician deflates the ballooncatheter and withdraws the cystoscope, including the deflated ballooncatheter and rod lens, from the patient.

Upon positioning internally as described above, the valve assembly 10 isautomatically activated in response to physiologic conditions and thuscan be controlled voluntarily by the patient without manualintervention.

As needed, the valve assembly 10, 110 can be removed from the patientand replaced with a new valve assembly. Removal of the valve assemblycan be accomplished in a variety of ways, including through use of thecystoscope 221, rod lens 229, grasping forceps 225 and/or embolectomyballoon catheter described above. For example, the grasping forceps 225are used to grasp the tab 27. The valve assembly can then be drawn intothe distal end of a tubular structure such as a channel in thecystoscope 221. Preferably, the valve is drawn into the cystoscope whilethe cystoscope is simultaneously advanced in the distal direction toavoid pulling the first anchor through the bladder neck.

Alternatively, the valve assembly can be pushed distally from itsinstalled position into the bladder, using the grasping forceps 225, rodlens 229 or other pushing structure. Preferably the physician will keepa grasp on the valve assembly such as by tab 27 using forceps 225throughout the proximal displacement step. Once the valve assembly is inthe bladder, it can be pulled into the end of the cystoscope. Withcertain anchor designs, the anchor may simply be pulled transurethrallyfrom the patient.

For convenience, the methods of positioning and removal described abovewere discussed with reference to valve assembly 10, 110. One of ordinaryskill in the art will recognize, however, that the methods ofpositioning and removal described above can also be used with otherembodiments of the present invention described in the subjectapplication.

Referring to FIGS. 18-20, there is shown an alternate embodiment of thepresent invention. The device 210 includes a tubular body 212 having aproximal end 218, a distal end 220 and a central lumen 222 extendingtherethrough. The device 210 also includes a first anchor 214, agripping boss 227 and reinforcing rings 215, 217.

In addition to the first anchor 214, the device 210 may also include asecond anchor 216. The structure and function of the second anchor 216illustrated in FIGS. 18-20 is generally similar to that of thepreviously described embodiments of the present invention.

The device 210 preferably does not include a discrete valve. One ofordinary skill in the art will recognize, however, that the device 210could include a discrete valve, such as those previously described inthe subject application.

The device 210 functions primarily as a bulking agent or sealing device,which reversibly seals by collapsing at least part of the tubular bodyin response to the previously described inwardly directed urethralforces. These forces on the urethra help to cause the tubular body tocollapse and seal when micturition is undesired, thereby maintainingurinary continence. Conversely, when micturition is desired, thepressure exerted by the urethra and bladder neck decreases, therebyallowing the tubular body to open.

The tubular body 212 of the device 210 can also function as a reversibleseal by kinking due to for instance bending of the tubular body inresponse to the previously described rotational descent of the bladderneck and urethra, such as during a hypermobility event.

The dimensions and configuration of the device 210 are generally similarto those of the previously described embodiment illustrated in FIGS.8-15. The tubular body 212 may be longer and have a thicker wall,however, in order to enhance the device's ability to serve as a bulkingagent, yet still take advantage of the urethral pressure gradient andother previously discussed aspects of urinary anatomy/physiology.

Typical ranges for the length of the tubular body portion 212 of thedevice 210 are approximately 1.0-3.0 cm, preferably about 1.0-2.0 cm.Typical ranges for the outside diameter of the tubular body 212 andsecond anchor 216 are generally similar to those of the previouslydescribed embodiments of the present invention. Typical ranges for thewall thickness of the tubular body 212 of the device 210 areapproximately 0.15-3 mm, preferably about 0.2 or 0.4-1.5 mm, and morepreferably about 0.4 or 0.5 mm. The tubular body 212 of the device 210can also have a variable thickness wall as previously discussed, whereinthe wall of the proximal portion of the tubular body is thinner thanthat of the distal portion to facilitate kinking of the proximalportion, such as a during a hypermobility event. In addition, aspreviously discussed, in order to facilitate kinking, the tubular bodycan have a non-circular cross section, such as elliptical or oval, atthe desired point of kinking or throughout the length of the tubularbody.

As will be apparent to one of skill in the art, the device 210 can bemanufactured in accordance with any of a variety of techniques andmaterials, such as those previously described. Also as discussed above,in addition to anatomical considerations, the size and shape of variouscomponents of the device 210 are governed by the type of material usedto construct the device. For instance, particularly compliant materials,such as the silicone rubbers and other materials described above,facilitate urethral compression and/or kinking of the tubular body ofthe device, especially in devices having a thicker walled tubular body.

As with the previously described embodiments of the present invention,one of ordinary skill in the art will recognize that a variety ofstructures other than the first anchor 214 and second anchor 216 couldbe used in accordance with the device 210. One of ordinary skill in theart will also recognize that any of a variety of installation andremoval techniques, including those described in the subjectapplication, could be used to position the device 210 within the urinarytract of the patient and/or to remove the device therefrom.

Referring to FIGS. 21-25 and 27, there is shown an alternativeembodiment of the present invention. The device 310 includes a tubularbody 312 having a proximal end 318, a distal end 320 and a central lumen322 extending therethrough.

As illustrated in FIG. 67, a tether 357 may be attached at the distalend 320 of the tubular body 312 to facilitate transurethral placement ofthe device. As will be apparent to one of ordinary skill in the art, atether may also be used with the other embodiments of the inventiondescribed in the subject application.

Preferably, the tether 357 is a removable suture so that after thedevice has been positioned, the suture can be removed to decrease therisk of infection. The tether 357 may also comprise a non-removablesuture or be an extension of the tubular body itself. If the tether 357is a non-removable suture or extension of the tubular body, care shouldbe taken to ensure that the tether does not extend beyond the urethralmeatus in order to minimize the risk of infection. In those cases inwhich a non-removable tether is used, the tether 357 may also be used tofacilitate removal of the device.

Alternatively, the tubular body 312 may include a gripping tab or bosssimilar to that of the previously described embodiments of the presentinvention in order to facilitate transurethral placement and removal ofthe device.

The device 310 also includes a first anchor 314. The first anchor 314preferably has an increasing diameter in the proximal direction andconforms to the bladder neck and/or proximal urethra. The outer diameterof the first anchor 314 at its proximal end 331 is preferablyapproximately 0.5-2.0 cm, more preferably about 0.8-1.3 cm.

The first anchor 314 functions to releasably secure the device 310relative to the bladder neck and urethra. The first anchor 314 alsohelps prevent urine from escaping around the exterior of the device.When positioned intraurethrally, as illustrated in FIG. 66, the firstanchor also serves a bulking/sealing function as discussed more fullybelow.

The first anchor is preferably an atraumatic retention structure whichis enlargeable from a first, collapsed configuration for transurethralplacement to a second, enlarged configuration for anchoring the device310 relative to the bladder neck and/or urethra. In the embodimentillustrated in FIGS. 21-25 and 27, the first anchor 314 comprises apliable generally circular retention structure that inclines generallyradially outwardly in the proximal direction from the proximal end 318of the tubular body 312 as illustrated in FIGS. 21, 23 and 25. Theretention structure is mechanically biased in the direction of thesecond, enlarged configuration as illustrated to help prevent the device310 from being displaced after positioning of the device in the patientas well as to help prevent urine from escaping around the exterior ofthe device.

Although shown as radiused in FIGS. 21 and 23, the first anchor 314 ofthe device 310 can also extend outwardly in a conical shape in theproximal direction from the proximal end 318 of the tubular body 312 asillustrated in an alternate preferred embodiment of the presentinvention depicted in FIG. 23A. The outer diameter of the conical-shapedfirst anchor 314 at its proximal end 331 is preferably approximately0.5-2.0 cm, more preferably about 0.8-1.3 cm.

The first anchor 314 can also be formed in a variety of other shapes,including the oval-shaped first anchor 314 illustrated in FIGS. 32-34and the star-shaped first anchor 314 illustrated in FIGS. 35-38. Thedimensions of the oval-shaped first anchor 314 at its proximal end 331are preferably approximately 0.3 cm along the short axis by 1.0 cm alongthe long axis, more preferably approximately 0.4 cm along the short axisby 0.7 cm along the long axis.

With regard to the star-shaped first anchor 314 illustrated in FIGS.35-38, the diameter of a circle drawn through the outer points 356 ofthe star-shaped first anchor 314 at its proximal end 331 is preferablyapproximately 0.5-2.0 cm, more preferably about 0.8-1.3 cm. The diameterof a circle drawn through the inner points 359 of the star-shaped firstanchor 314 at its proximal end 331 is preferably approximately 0.3-1.8cm, more preferably about 0.6-1.1 cm.

In addition to the first anchor 314, the device 310 optionally mayinclude a second anchor 316 to further releasably secure the device 310and stabilize the tubular body 312 within the urethra. In the embodimentof the device illustrated in FIGS. 21-25 and 27, the second anchor is adual annular flange that extends radially outwardly in both the proximaland distal directions. The distance between the most proximal and mostdistal portions of the second anchor 316 measured along the longitudinalaxis of the tubular body 312 can vary, but is preferably approximately0.2-0.8 cm, more preferably about 0.4 cm. Optionally, one or morenitinol rings can be molded into the annular flange as previouslydiscussed.

In the illustrated embodiment, the second anchor 316 is located alongthe length of the tubular body between the first anchor 314 and thedistal end 320 of the tubular body 312. In such cases, the location ofthe second anchor 316 can vary, but preferably the midpoint of thesecond anchor 316 measured along the longitudinal axis of the tubularbody 312 is approximately 0.2-0.8 cm from the proximal end 318 of thetubular body 312, and more preferably about 0.40 cm from the proximalend 318 of the tubular body 312. In addition, the distance between themost proximal portion of the second anchor 316 and the proximal end 331of the first anchor 314 is preferably approximately 0.4-1.2 cm, morepreferably about 0.8 cm.

Alternatively, the second anchor 316 may extend distally from the distalend 320 of the tubular body 312 as illustrated in FIG. 26. The structureand location of the second anchor 316 can also be generally similar tothat of the previously described embodiments of the present invention.

The devices of the present invention, such as the device 310 may alsoinclude radiopaque markers 355 such as those illustrated in FIGS. 21-23,25-26 and 32-33 to ensure proper positioning of the device, includingrotational orientation. In the illustrated embodiments, the device hasthree markers 355 on the first anchor 314 and one marker 355 at theproximal end 318 of the tubular body 312. The preferred radialorientation of the markers 355 is shown in FIGS. 21-23, 25-26 and 32-33.One of skill in the art will recognize that any of a number of types ofradiopaque markers 355, such as gold, tantalum or barium sulfate, andradial orientations may be used to ensure proper positioning of thedevice 310. In addition, the markers 355 can be included in portions ofthe device 310 other than the first anchor 314 and proximal end 318 ofthe tubular body 312. As will be apparent to one of ordinary skill inthe art, the markers 355 can be incorporated into the device 310 orattached to the device 310 in a number of ways. The markers 355 arepreferably bonded to the device 310 using silicone, such as roomtemperature vulcanizing silicone (NuSil MED 2000).

The device 310 preferably does not include a discrete valve. One ofskill in the art will recognize, however, that the device 310 couldinclude a discrete valve, such as those previously described in thesubject application.

As discussed above with regard to the embodiment of FIGS. 18-20, thedevice 310 functions preferably as an intraurethral bulking agent, whichreversibly seals in response to the previously described inwardlydirected urethral forces. These forces on the urethra help to collapseand seal the tubular body 312 and/or first anchor 314 when micturitionis undesired, thereby maintaining urinary continence by augmentingnatural urethral sealing. Conversely, when micturition is desired, thepressure exerted by the urethra and bladder neck decreases, therebyallowing the tubular body and first anchor to open. Thus, the presentinvention provides a dynamic device which changes in response to naturalinternal forces, such as physiologic and anatomic forces acting upon theurethra and/or bladder neck.

The tubular body 312 of the device 310 can also function as a reversibleseal by kinking due to for instance bending in response to thepreviously described rotational decent of the bladder neck and urethra,such as during a hypermobility event.

A typical range for the length of the tubular body 312 of the device 310as provided to the physician is approximately 0.5-5.0 cm. As discussedmore fully below, if necessary, the tubular body 312 is cut by thephysician so that the length of the device 310 is preferablyapproximately 0.2-1.0 cm less than the patient's measured urethrallength, more preferably about 0.60 cm less than the patient's measuredurethral length. Typical ranges for the outside diameter of tubular body312 are preferably approximately 0.20-0.80 cm, more preferably 0.40-0.60cm. Typical ranges for the outside diameter of the second anchor 316 arepreferably approximately 0.50-1.0 cm, more preferably 0.60-0.90 cm.Typical ranges for the wall thickness of the tubular body of the device310 are approximately 0.30-0.80 mm, preferably about 0.40-0.60 mm, andmore preferably about 0.50 mm.

The tubular body of the device can also have a variable thickness wallas previously discussed, wherein the proximal portion of the tubularbody is thinner than that of the distal portion to facilitate kinking ofthe proximal portion, such as during a hypermobility event. In addition,as previously discussed, in order to facilitate kinking and sealing, thetubular body can have a non-circular cross-section, such as ellipticalor oval, at the desired point of kinking or throughout the length of thetubular body.

A variety of tubular bodies having a non-circular cross-section areshown in FIGS. 28-31. The shape of the tubular body 312 optimallysimulates the patient's natural urethral shape while restoring lostfunction without causing urinary obstruction.

FIGS. 30 and 31 illustrate an additional optional feature of the presentinvention. In particular, the tubular body 312 illustrated in FIGS. 30and 31 has a stiffened posterior floor 361, which can be provided usinga variety of conventional manufacturing techniques. FIG. 30 shows thetubular body in a closed position while FIG. 31 shows the tubular bodyin an open position. As can be seen, the shape of the stiffenedposterior floor 361 remains relatively constant while the rest of thetubular body expands from the closed position to the open positionduring micturition. In addition, the stiffened posterior floor 361 actsas a backstop for downwardly directed abdominal pressure to helpmaintain continence during increases in abdominal pressure, such asduring coughing.

A variety of first anchor types, second anchor types, and tubular bodytypes have been described in the subject application in relation tospecific embodiments of the present invention. One of ordinary skill inthe art will recognize that these and other aspects of the presentinvention can also be combined in a variety of manners other than thecombinations specifically described.

As will be apparent to one of skill in the art, the device 310 can bemanufactured in accordance with any of a variety of techniques andmaterials, such as those previously described. Also as discussed above,in addition to anatomical considerations, the size and shape of variouscomponents of the device 310 are governed by the type of material usedto construct the device. For instance, particularly compliant materials,such as silicone rubbers and other materials described above, facilitateurethral compression and/or kinking of the tubular body 312 of thedevice 310, especially in devices having a thicker walled tubular body.A preferred material for the device 310 is Dow Silicone, MDX4-4210.

As with the previously described embodiments of the present invention,one of ordinary skill in the art will recognize that a variety ofstructures other than the first anchor 314 and second anchor 316 couldbe used in accordance with the device 310. One of ordinary skill in theart will also recognize that any of a variety of installation andremoval techniques, including those described in the subjectapplication, could be used to position the device 310 within the urinarytract of the patient and/or to remove the device therefrom.

The various embodiments of the present invention, such as device 310,may also include a resilient support structure 463 as illustrated inFIGS. 39-45 to provide an additional mechanical bias to help furthersecure the device within the patient. The resilient support structure463 can also be used with other tubular devices as will be apparent toone of ordinary skill in the art.

Depending on the shape of the resilient support structure 463, it canalso be used to bias the tubular body 312 of the device 310 towards aflattened/closed shape as illustrated in FIGS. 41-42 and 44-45 to helpmaintain continence without causing urinary obstruction. In addition,the resilient support structure provides some rigidity to minimizedistortion of certain portions of the device during increases inabdominal pressure.

The resilient support structure 463 can be incorporated into the device310 as illustrated in FIGS. 39 and 40. The resilient support structure463 can also be inserted into the lumen of the device 310 as illustratedin FIGS. 41-42 and 44-45. In the devices illustrated in FIGS. 41-42 and44-45, the bias of the resilient support structure 463 against thetubular body 312 of the device 310 holds the resilient support structure463 in place relative to the device 310. The resilient support structure463 shown in FIGS. 41-42 and 44-45 can also be secured to the device 310using conventional techniques such as thermal bonding, solvent bondingor suitable adhesive known in the art.

The resilient support structure 463 can also be used alone asillustrated in FIGS. 46-48. In FIGS. 46 and 47, the urethra 40, bladderneck 42, and a portion of the bladder 30 are shown schematically inphantom. In the embodiment of the present invention illustrated in FIGS.46-48, a portion of the resilient support structure 463 extends into thebladder to help secure the resilient support structure 463 within theurinary tract. In other cases, the resilient support structure 463 mightbe totally intraurethral or extend only from the urethra to the bladderneck as opposed to extending into the bladder. The resilient supportstructure 463 is preferably shaped so that it exerts a biasing forceagainst the urethra to further secure the resilient support structure463 within the urinary tract as well as to bias the urethra towards aflattened cross-sectional shape to help maintain continence.

The resilient support structure 463 of FIGS. 39-48 preferably comprisestwo axially extending segments 464 and 466 extending from a first endportion 468. The resilient support structure 463 may also include asecond end portion 470. The distance separating the first axiallyextending segment 464 from the second axially extending segment 466 ispreferably greater than the diameter of the urethra to help anchor theresilient support structure 463 therein. The first and second axiallyextending segments 464 and 466 may also be curved as illustrated inFIGS. 43 and 48 so that after the resilient support structure 463 ispositioned in the patient, a portion of the urethra is biased in thecephalad direction.

The first end portion 468 of the resilient support structure 463 maycomprise a loop of varying shapes as illustrated in FIGS. 39, 41, 46 and47. The first end portion 468 may have a diameter which is greater thanthe distance separating the first axially extending segment 464 from thesecond axially extending segment 466 to further anchor the resilientsupport structure 463, especially in those embodiments of the presentinvention in which the first end portion 468 of the resilient supportstructure 463 extends into the bladder neck and/or into the bladder.

The dimensions of the resilient support structure 463 of FIGS. 39-48 arelargely governed by anatomical considerations and the size/shape of thedevice, if any, with which it is being included. One of ordinary skillin the art will recognize that a variety of sizes and shapes other thanthose illustrated for the resilient support structure 463 could be usedin accordance with the present invention.

The resilient support structure 463 may be made of any suitableresilient material. Preferred materials include stainless steel,nitinol, titanium, and polymeric materials, such as polyurethane andpolypropylene.

One of ordinary skill in the art will recognize that any of a variety ofinstallation and removal techniques, including those described in thesubject application, could be used to position devices having aresilient support structure 463, such as the devices illustrated inFIGS. 39-45, within the urinary tract of the patient and/or to removesuch devices therefrom.

One of ordinary skill in the art will also recognize that theinstallation and removal techniques described in the subject applicationcan also be used to position the resilient support structure 463 ofFIGS. 46-48. In such cases, however, instead of releasably engaging thedistal end of a tubular body, the device of FIGS. 46-48 is preferablyreleasably engaged with grasping forceps generally at the second endportion 470 of the resilient support structure 463 to position thedevice of FIGS. 46-48 within the urinary tract of the patient and/or toremove the device therefrom.

Another aspect of the present invention relates to an introducer 580illustrated in FIGS. 55-59. The introducer 580 can be used as a conduitto pass a variety of devices into or through a body lumen or orifice totreat a variety of conditions. For example, the introducer 580 can beused to transurethrally position a variety of urological/gynecologicaldevices, including the devices of the present invention such as device310.

The introducer 580 is an elongate generally tubular structure having afirst end 581, a second end 582, and a variable diameter central lumen588 extending therethrough. The variable diameter feature of the centrallumen 588 may be present along the entire length or along a portion ofthe length of the introducer 580. The introducer 580 also has an uppersurface 583 and a lower surface 584.

The introducer 580 may also have a handle. The handle may be located ata variety of positions along the length of the introducer 580.Preferably, the handle is located at the second end 582 of theintroducer 580.

The wall of the introducer 580 preferably has a longitudinally extendingsplit 585, which extends from the first end 581 at least partially alongthe length of the wall of the introducer. Preferably, the longitudinallyextending split 585 extends at least 2 cm from the first end 581 of theintroducer 580. More preferably, the longitudinally extending split 585extends from the first end 581 to the second end 582 of the introducer580 as illustrated in FIG. 56. The split wall allows the introducer 580to expand (FIG. 58) and contract or overlap (FIG. 59) relative to itsresting state (FIG. 57). Expansion of the introducer 580 facilitatesloading and deployment of the device 310 and minimizes distortion of thedevice 310 during loading and deployment thereof. To further facilitateexpansion of the introducer 580, the second end 582 in the area of thesplit 585 can be chamfered approximately 0.1 cm by 45° at two places asillustrated at reference numeral 586 of FIG. 56. Contraction oroverlapping of the walls of the introducer 580, such as in response asradially inwardly directed urethral forces during transurethralplacement, minimizes the profile of the introducer 580, therebyminimizing urethral trauma and patient discomfort. In addition, theedges of the introducer 580 are smoothed using conventionalmanufacturing techniques to minimize urethral trauma.

The introducer 580 can be made from a variety of materials, includingpolymers such as cellulosics, polyesters and polyolefins. A preferredcellulosic material for the introducer 580 is Cellulose AcetatePropionate (CAP), which can be purchased from Eastman under the brandname "Tenite."

The first end 581 of the introducer 580 also preferably has anatraumatic tip 587 as illustrated in FIG. 55. The atraumatic tip 587 canbe formed from a variety of materials, including the material used toconstruct the introducer 580. Preferably, the atraumatic tip 587 isformed with silicone, such as room temperature vulcanizing silicone(NuSil MED 2000). Small holes can be drilled into the first end 581 ofthe introducer 580 to facilitate attachment of the atraumatic tip 587,such as when the atraumatic tip 587 is formed with silicone.

The dimensions of the introducer 580 largely depend on anatomicconsiderations, the size of the device being inserted through theintroducer, and the material used to construct the introducer. Thelength of the upper surface 583 of the introducer 580 is preferablyapproximately 8.0-14.0 cm, more preferably about 12.0 cm. As illustratedin FIG. 55, the length of the upper surface 583 is preferably greaterthan the length of the lower surface 584 so that the first end 581slopes upwardly relative to the longitudinal axis of the introducer 580at approximately a 30° angle. The outer diameter of the introducer 580is preferably approximately 0.50-1.0 cm, more preferably about 0.70 cm.The wall thickness of the introducer 580 is preferably approximately0.30-1.0 mm, more preferably about 0.50 mm. If an atraumatic tip 587 isincluded, it preferably extends longitudinally along the wall of theintroducer 580 approximately 1.0-3.0 mm, more preferably about 2.0 mm.

An alternative nonsurgical or minimally invasive procedure forpositioning an intraurethral device within the flow path between thebladder and the introitus to maintain urinary continence in a patientusing the introducer 580 is generally accomplished as follows. Forconvenience, the following positioning and removal procedures will bedescribed with reference to device 310. One of skill in the art willrecognize, however, that these positioning and removal procedures can beused with a variety of devices, including the other embodiments of thepresent invention described in the subject application.

The urethral length is measured from the bladder to the introitus usinga balloon measurement catheter or other conventional measuringtechniques. A device for maintaining urinary continence, such as device310, is selected by the physician. If necessary, the tubular body 312 iscut to length by the physician based on the patient's measured urethrallength so that the length of the device 310 is tailored to theindividual patient. Preferably the tubular body 312 is cut so that thelength of the device 310 is preferably approximately 0.2-1.0 cm lessthan the measured urethral length, more preferably about 0.6 cm lessthan the measured urethral length.

A releasable engaging device, such as grasping forceps 225, is passedthirough the lumen 588 of the introducer 580 to releasably engage thedevice 310. The forceps can releasably engage the distal end 320 of thetubular body 312 directly, or can engage a gripping boss/tab or a tether357 attached to the tubular body.

Using a coupling device, preferably a releasable coupling device such asa C-clip 291, the shaft 295 of the forceps 225 is attached to the shaftof a locating device having an expandable tip, such as a ballooncatheter 290. Preferably, the shaft 295 of the forceps 225 is attachedto the shaft 292 of the balloon catheter 290 so that the shoulder 293 ofthe balloon 294 of the balloon catheter 290 is separated by a distance"L" from the proximal end 331 of the first anchor 314 of the device 310as illustrated in FIGS. 60-65. The distance "L" can be varied dependingon where in the urinary tract the physician wants to anchor the device310. The distance "L" may also be adjusted if a non-releasable couplingdevice is used, such as by sliding the shaft of the balloon catheterrelative to the shaft of the forceps. Preferably "L" is approximately1-7 mm, more preferably about 3-7 mm so that the first anchor 314 of thedevice 310 lodges in the bladder neck and/or proximal urethra.

The outside of the device 310 and balloon catheter 290 are lubricatedwith a water soluble lubricant, such as K-Y jelly and gently withdrawninto the introducer 580 as illustrated in FIG. 60. The introducer 580 isthen passed into the urethra 40 so that the first end 581 of theintroducer 580 extends into the bladder 30 as illustrated in FIG. 61.

FIG. 61 also schematically illustrates the external urethral sphincter46 and the internal urethral sphincter 44. In the female anatomy, theexternal urethral sphincter is difficult to distinguish. In the subjectapplication, the external urethral sphincter is understood to includethe urethral tissue immediately proximal to the urethral introitus. Inthe subject application, the internal urethral sphincter is intended toinclude the tissue at the urethro-vesical junction, also referred to asthe bladder neck.

FIGS. 62-63 illustrate the device 310 and balloon catheter 290 beingcarefully pushed out of the introducer 580 and into the bladder 30. Asillustrated in FIG. 64, the introducer 580 is then withdrawn from theurethra 40 and the balloon 294 is inflated using conventional inflationmedia, such as water. The coupled grasping forceps 225 and ballooncatheter 290 are then carefully withdrawn until the inflated balloon 294contacts the bladder neck 42 a illustrated in FIG. 65. At this point,the proximal end 331 of the first anchor 314 resides within the bladderneck and/or proximal urethra the pre-selected distance "L" from theshoulder 293 of the inflated balloon 294.

The balloon 294 is deflated and the shaft 295 of the grasping forceps225 is decoupled from the shaft 292 of the balloon catheter 290. Theballoon catheter 290 is removed from the patient, the device 310 isreleased from the grasping forceps 225, and the grasping forceps areremoved from the patient, leaving the device 310 properly positionedwithin the urinary tract of the patient as illustrated in FIG. 66. If anon-releasable coupling device is used, the balloon 294 is deflated, thedevice 310 is released from the grasping forceps 225, and the coupledgrasping forceps 225 and balloon catheter 290 are removed simultaneouslyfrom the patient, leaving the device 310 properly positioned within theurinary tract of the patient.

Preferably the entire device 310 is positioned within the urethra. Thedevice 310 is held in place due to the natural compliance of the urethra40. Optionally, the position of the device 310 can be confirmed usingwell-known radiologic methods, such as in those embodiments whichinclude radiopaque markers 355.

FIGS. 68-69 illustrate the device 310 placed in an alternative position.The position of the device in the urinary tract is related to a numberof factors, such as the etiology of the patient's incontinence and thetype of device being using to treat the patient. As illustrated bycomparing FIGS. 65-66 to FIGS. 68-69, by varying the position of theshoulder 293 of the balloon 294 in relation to the proximal end 331 ofthe first anchor 314 prior to coupling the shaft 295 of the graspingforceps 225 to the shaft 292 of the balloon catheter 290, the physiciancan accurately place the device 310 in any of several desired positionsin the urinary tract.

The devices of the present invention, such as device 310, can also bepositioned within the urinary tract fluoroscopically. As discussedabove, after measuring the urethral length, the tubular body of thedevice is cut to length by the physician. The bladder is filled withcontrast fluid. The distal end of the device 310 is releasably engagedusing grasping forceps 225 as discussed above. The outside of the device310 is lubricated with a water soluble lubricant, such as K-Y jelly andgently withdrawn into the introducer 580 as previously discussed. Theintroducer 580 is then passed into the urethra so that the proximal endof the introducer extends into the bladder as discussed above. Thedevice 310 is carefully pushed out of the introducer 580 and into thebladder while still be held by the grasping forceps 225. The introduceris then withdrawn from the urethra. Under fluoroscopic control, thedevice 310 is then withdrawn into the urethra until the first anchor 314is observed to be just within the bladder neck, which is indicated byvisualizing an inward movement of the radiopaque markers 355 on thefirst anchor 314 as it enters the urethra. The device 310 is thenreleased from the grasping forceps and the grasping forceps are removedfrom the patient, leaving the device properly positioned within theurinary tract. Optionally, the position of the device is reconfirmedfluoroscopically after having the patient perform a variety ofconventional maneuvers and exercises, including those which increaseabdominal pressure.

As needed, the devices of the present invention can be removed from thepatient and replaced as previously discussed. Because the device 310does not contain any protruding sharp or rigid elements, if an emergencyarises, such as an obstruction, the device 310 can be pushed into thebladder using a conventional catheter, such as a Foley catheter withoutcausing damage to the urethra or bladder. The device 310 can remain inthe bladder without causing any complications until the patient is ableto see their physician for removal and replacement of the device.

Although this invention has been described in terms of certain preferredembodiments, other embodiments which will be apparent to those ofordinary skill in the art in view of the disclosure herein are alsowithin the scope of this invention. Accordingly, the scope of theinvention is intended to be defined only by reference to the appendedclaims.

What is claimed is:
 1. A combination of a device for treating urinaryincontinence and an introducer for transurethrally introducing thedevice, said combination comprising:a device for treating urinaryincontinence; and an introducer, wherein said introducer is an elongategenerally tubular structure having a first end, a second end, and acentral lumen extending therethrough, said tubular structure having avariable diameter so that said tubular structure can expand tofacilitate loading and deployment of the device and contract duringtransurethral introduction of the device to minimize urethral trauma andpatient discomfort.
 2. The combination of claim 1, wherein said tubularstructure has a wall with a split which extends partially along thelength of the wall.
 3. The combination of claim 1, wherein said split inthe wall of said tubular structure extends longitudinally from the firstend of said tubular structure to the second end of said tubularstructure.